import java.util.PriorityQueue;

class MyTimerTask implements Comparable<MyTimerTask>{
    private Runnable task;
    private long time;
    public MyTimerTask(Runnable task,long time) {
        this.task = task;
        this.time = time;
    }

    @Override
    public int compareTo(MyTimerTask o) {
        return (int) (this.time-o.time);
    }
    public long getTime(){
        return time;
    }
    public void run(){
        task.run();
    }
}
class MyTimer {
    private PriorityQueue<MyTimerTask> queue = new PriorityQueue<>();

    private Object locker = new Object();
    public void schedule(Runnable task,long delay){
        synchronized (locker){
            MyTimerTask timerTask = new MyTimerTask(task,System.currentTimeMillis()+delay);
            queue.offer(timerTask);
            locker.notify();
        }

    }

    public MyTimer() {
        Thread t = new Thread(()->{
            try {
                while (true){
                    synchronized (locker){
                        while(queue.isEmpty()){

                            locker.wait();

                        }
                        MyTimerTask task = queue.peek();
                        if(task.getTime() > System.currentTimeMillis()){
                            locker.wait(task.getTime()-System.currentTimeMillis());
                        }else {
                            task.run();
                            queue.poll();
                        }
                    }
                }
            } catch (InterruptedException e) {
                throw new RuntimeException(e);
            }
        });
        t.start();
    }
}
public class Test2 {
    public static void main(String[] args) {
        MyTimer timer = new MyTimer();
        timer.schedule(new Runnable() {
            @Override
            public void run() {
                System.out.println("hello");
            }
        },1000);
    }
}
